cel.... cylinder 1,3,4 misfire???

I reset my check engine light the drive to work, 49 miles, no light. drive home half way cel. same. the d16y7 has 160,000 miles just did the plugs still happens what else could it be. i still have the wires and cap and rotor left to do but does any one think that is the problem

are you throwing a P1300 code? I have misfires in 3 cylinders and a P1300 random misfire code. I replaced plugs, wires, cap and rotor and still have the problem (came back after 15 miles). Put a used ignitier my friend had in, ran better (codes came back when i pulled a steep hill after 150 miles of straight driving). Just realized my battery terminals were insanely loose... i could lift them off with no resistance. I replaced those and it idled perfect, no misfire. I'm going to take it for a nice drive today. i'll let you know how it goes.